Lifting-jack.



No. 657,514:I Patented sept. n, |900.

A. L. coB'B.

LIFTING JACK.

(Application mamme 4, 1900.;

(No Model.)

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i ,NTfED STATES PATENT OFFICE?.

ALFRED L. COBB, OF BOULDER, COLORADO, ASSIGNOR OF ONE-HALF TO JAMES COWIE, OF SAME PLACE;

LlFTlNe-JACK.

srn'eIFIcATIoN aiming part of Letters Patent No. 657,514, dated septembe 11, 1966.

Application filed .Tune 4, 1900. v

rado, have invented a new and useful Lifting- Jack, of which the following is a specification.

- The invention relates to improvements in lifting-jacks.

The objects of the present invention are to improve the construction of lifting-jacks and.

to provide a simple and inexpensive and effi! cient one of that class which employs a screw and to enable the latter to be readily rotatedA independently of the supporting head or portion and to exclude dust eifectually from the bearings.

The invention consists inthe construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings, and pointed out in the claims hereto appended.

In the drawings, Figure lis a vertical sectional view of a lifting-jack constructed in accordance with this invention. Fig. 2 is a detail perspective view of the upper port-ion of the screw.l Fig. 3 is a similar `view of the supporting head or cap, the same being inverted. Fig. 4 is a detail view of the securing-nut, showing the same inverted.

Like numerals ot' reference designate corresponding parts in all the figures of the drawings.

l designates a tubularstandard provided with an interiorly-threaded upper portion 2, forming a fixed nut and receiving a jackscrew 3, which is provided at its upper end with a rounded enlargement 4, adapted to be engaged by a bar or lever for rotating the screw. The rounded enlargement 4, which extends outward beyond the edges of the top of the tubular standard, is provided with, horizontal transverse openings 5, arranged'at right angles to each other and adapted to re`- ceive the actuating bar or lever.

The upper face of the cylindrical enlargement 4is provided with an annular'fgroove 6, extending around a Vertical stud 7 and forminga ball-race for the reception of a series of antifriction-balls 8, which are interposed between the upper face of the cylindrical enlargement and the lower face of a supportserai No. 19,021. (No model.)

` 4ing cap or head 9. The cap orhead, which is cylindrical, is provided with a central opening, and it has an annular groove 10 at its lower face Afor the reception of the antifriction-balls 8. The bottom of the supporting cap or head is provided atits periphery with la depending flange 11, extending below the upper face of the cylindrical enlargement 4 to provide a shield for excluding dust from `the adjacent ball-bearings.

The stud 7, which is formed integral with, the enlargement of the screw, is provided The smooth portion fits latter rotates. The upper portion of the aperture of the cap orhead is enlarged at a :point below the threadedportion 1,3 of the stud to form a shoulder 14, which is provided with an annular groove to form a ball-race for the reception of a'n annular series `of antifriction balls 15 of less diameter than the lower balls 8 and interposed between the said `shoulder and a securing-nut 16. 'lhe eX- trelne -upper portion of the aperture of the supporting head or'cap is flared at 17 to re ceive an enlargement or projecting portion 1,8 of the securing-nutrl, which is located wholly beneath the upper face of the supporting head or collar, as clearly illustrated in Fig. l of the accompanying drawings.'

The securing-nut 16, which is provided at its top with an exteriorpolygonal wrench-receiving enlargement 18a, has screw-threads 19 at the upper `portion of its interior to engage `the screw-threads of the stud 7, and it forms a cap for the said stud. The lower portion 20 of the interior `of the secu ring-nut is smooth, and an annulargroove 2l is provided at the lower edge of the nut to receive the upper small antifriction-balls 15, and by the arrangement of the upper and lower `ballbearings the screw may be rotated freely without liability of accidentally un'screwing the securing-nut. The projecting portion, which extends from the periphery of the nut to the top thereof, has an inclined lower face to agree with the flare of the top portion of the opening or aperture of thesupporting IOO cap or head, and lby this construction a dustproof bearing is provided. The vouter face of the securing-nut and' the adjacent walls of the central aperture of the supportinghead or cap are smooth, and the upper face of the head or c'ap is grooved or corrugated to prevent it from slipping on the part to be 'ele-i vated. These grooves or corrugations 'may be formed in any suitable manner, as will b readily apparent'. I

ing head or cap.

bearings perfectly dust-proof.

What is claimed isy l. A lifting-jack comprising a standard, a

central aperture extending entirely through the head or cap and receiving the stud, the f upper portion of the aperture beingenlarged to provide a shoulder, and a securing-nut 1oca-ted'wholly within the Aupper portion of Ithe aperture of the supporting header cap, engagin g the screw-threads of fthe stud, and hav-"f ing its lower edge located directly above the said shoulder, whereby thejcapor head isjretained i'n position, said "Ifft'bein'g provided at its upper face with 'aWrenchreceivi'rlg'jerp largement located within the central laperture -of the head or `cap',subst'an"tial-ly "as described. Y j

'2; Ar lifting-jack comprising a standard, ia screw having an enlargement, avertical stud projecting from thes'aid enljargernentatthe vtop thereof and provided with'a threaded u py perportion and a smooth lower portion, fa

supporting head or cap arranged'on thestud and having a central aperture to receive the same; the upper portion of the aperture be#l ing enlarged to provide a shoulder, and the latter having an annular groove forming a ball-race,- a securing-nut located Within the upper lportion of the aperture and having an interiorly-'threaded upper portion to engage the screw-threads of the stud, the lower portion ofthe nut being smooth and the bottom l of the nut being provided with an annular It will be seen that the liftingfjack is simple and comparatively inexpensive in its construction, that it possesses great kstrength `'and 1 durability, and that the jack-screw is adapted to rotate freely independently of the vsupp'or'tl It will also be apparent g that'the partsare arranged to render the ballgroove .located above the said groove, antifriction-balls arranged in the said grooves and interposed between the shoulder `of the cap' or headuand the lower edge of the securingnut, 'and antifriction devices Ainterposed between the cap or head and the `enlargement ofthescrew, substantially'as described.

u3. A lifting-jack comprisil-iga standard, a

jack-screw engaging the standardand hav ing va"cylintnrical enlargement, a vertical stud extending vfrom 'the top lof the enlargement kand provided with a threaded upper portion and a 'smooth lower portion, a 'supporting head or cap having a central aperture receiving the stud, enlarged to form a shoulder and provided with a flaring upper portion, said shoulder being grooved, a nut fitting over .and engaging theth're'ad ed 'portion ofthe stud and havin'gafn'annul'a'r groove at itsio'ottom and provided at'its top with a projecting peripheral port-ion Y,having an inclined lower face conforming to the configuration of the lflare of the-aperture 'the headfor'c'ap', balls i interposed betweenthe nut-,and the shoulder, and anti-fricl ion devices arranged ybetween vthe enlargement of thesc'rew and 'the `bottom offthe head `for cap,jsubstantially as de-A scribed.

In tettimony thatl claim Vthe foregoing as my Vown I have heretoalxe'd my signature .in

the presence fof two 'wi-tn'esses,

Y AALrrnrn L. ooBB.

d Witnesses; .i j y v J. P.- MAXWELL', RALPH r`LEECH.` 

